Thursday, June 12, 2014

The Big Bu(r)st! Cosmic Microwave Inflation....deflates

If a WorldView commentary by Paul Steinhardt, a Princeton physicist, in the June 5 issue of Nature is more reliable than much of what we find in Nature, the Big Story of the Big Bang was a Big Bust.  Remember the piece in the March 17 issue reporting that "Astronomers have peered back to nearly the dawn of time and found what seems to be the long-sought ‘smoking gun’ for the theory that the Universe underwent a spurt of wrenching, exponential growth called inflation during the first tiny fraction of a second of its existence"? Well, it turns out that this may not be true after all.  Or at least it's still being debated, as another Nature commentary in the same issue describes. The announced result, which Steinhardt writes influenced academic appointments and decisions on paper publications, funding, and the like, was apparently, he says, just a misinterpretation of the data, but forthcoming papers will carry on the discussion.

We personally know as little about cosmological physics as some people think we know about genetics, but even so we venture to say that (as the Commentary author pointed out) the treatment of the original report by the news media, and hence also by the reporting scientists, shows a lot about the (sorry) state of an important aspect of science today:  it is too much about advertising and too little about science.

In essence, if we look in all directions at the cosmic radiation we can detect reaching our area of space, it is very even--not very clumpy.  In a generic big bang theory, the space splatter that happened at the very beginning will eventually be brought by gravity back to its origin, with lots of clumps of matter (galaxies and the like) in the process.  But while there are on the order of 100 billion galaxies with about 100 billion stars each, plus lots of other rocks and matter and energy out there, and lots more dark matter and energy, everything is distributed far more uniformly throughout space than one might have expected.

But if, as Alan Guth suggested in the 1980s with his cosmic inflation theory, there was a burst of very rapid expansion way back just after the Big Bang itself, then this 'inflation' should have generated ripples in space-time, which we should detect as irregularities in what is now the cosmic microwave radiation reaching the earth which was reported to reflect, as we understand it, ripples in gravity due to this initial inflation 14 billion years ago.

History of the Universe - gravitational waves are hypothesized to arise from cosmic inflation, a faster-than-lightexpansion just after the Big Bang (17 March 2014). Wikipedia

The report of this finding of cosmic microwave ripples lent support to various aspects of cosmological theory and when breathlessly announced and picked up equally breathlessly by the media, talk of Nobel prizes, astounding discovery about the nature of everything, and so on were trumpeted from the media-tops.  Only a little skepticism or reserve was expressed by pundits and other cosmologists, who gushed with praise over this long-awaited report.

The problem is, apparently, that other sources of twisty microwave radiation exist that are unrelated to any early expansion and are more likely to account for the ripples that were reported.  There may be nothing inflationary there after all, or if there is something that survives scrutiny it may only be slightly more likely to be due to inflation than to other things.

Forgiving any errors in our above account, which aren't important to our objective, this is how things stand today. We note yet again the role that the media and hype-machinery are playing in today's science. The more important the claim, the more rigorous and extensive should be the evidence for the claim. In this case, the inflation-finding study was not even published when it was announced and picked up with great melodrama by the media.

Suppose one claimed that, after millennia of searching for more than just faith as evidence, s/he had definitive proof of God's existence.  For example, claiming that God had five fingers on each of two hands (we are, after all, said to be in his likeness and image) was proved because of how He enumerated the ten commandments.  For this claim to be accepted and reported as real, the evidence should be overwhelming, because if true the claim would fundamentally change how many of us view existence itself, and our place in it.  Such a truth would merit the most serious reception, as it would replace the less than satisfying "sure and certain hope" with something a bit more reassuring!  That someone reports some sort of evidence should not be given a splash, or even much if any mention, in public media.  It should be reported in a technical science journal, leading to focused and deliberate consideration, confirmation or elaboration, and so on, before it is accepted and reported as fact that fundamentally changes our worldview.

That might happen had we a more responsibly run, less self-promoting, environment. The inflation-evidence claim would have properly appeared, quietly, in a technical cosmology journal, peer-reviewed, where it could be scrutinized and built into more elaborate theoretical and empirical understanding.  It should be given measured acceptance that leads to focused attempts to test, refute, or elaborate it.  No big-splash press headlines, no drooling over obvious Nobel prizes, no advertising are merited at this stage. Indeed, the author of the Nature commentary notes the role of hype in the premature inflation announcement, and that, in his view, at least the theory that was supposedly confirmed by the gravitational ripples is untestable, even in principle, whether or not it's consistent  with any kind of data one could collect.  Nonetheless, the cosmology industry will not tuck its tail between its legs and go on to more effective, even if less expensive, questions that can actually yield believable answers, quietly, and not give them public blare until they are solidly established and really deserve the attention.

Large amounts of funding are manipulated by the current way of doing science.   It is hard not to believe that this is intentional on the part of all parties--the proverbial mutual reinforcement society.  We know from personal experience that it is this way, quite consciously, in genomics and other biomedical sciences.  Grand claims trump quiet, focused research on problems that might help peoples' lives but are not cosmic in scale--there are many such genetic problems that should be solvable.  As it is now, rather than careful guardians of the public purse, the funders themselves are part of the hype game, to make sure their portfolios stay full (or are subject to inflation!), an attitude which should not be tolerated. Investigators hungry for funds to support their work sing the song that will get them their supper. Claims and papers are put out, structured, and timed so they can be cited as justification for further funds.  We all know we are doing this--'all' except, perhaps, the public who's paying for it.  But science should avoid this sort of secret hypocrisy.

A million multiverses don't exist, nor does a cure for cancer, just because some hasty press release says so.  Major findings, when really real, deserve all the praise one can give them.  Science, actual real results rather than advertising, is interesting enough in itself without needing hype and can be made so to the public, without all the candy wrappers it comes in these days.  The world can wait until the evidence is really sufficient.  It isn't exactly urgent that we know whether there was cosmic inflation 14 billion years ago.  We don't urgently need to identify all genes contributing a fraction of a percent to diabetes risk (far less than the risk reduction by eating better).

Not even the Republican budget-cutters have yet caught on, but if we're lucky, the public will demand it.  Funding agencies should be threatened with deep cuts if they don't do their jobs properly, and that would at least possibly frighten scientists into doing more work and less boasting, even if it takes time and major results are more elusive.  A more modest way of doing, and reporting, science would be more responsible, and would make our careers more satisfying, especially for new entrants to look forward to.  As things are done now, we've built a system in which too many glittering Big Bursts turn into the ashes of Big Busts.

2 comments:

Anonymous said...

What I especially appreciated in Steinhardt's commentary was this recommendation that "announcements should be made after submission to journals and vetting by expert referees. If there must be a press conference, hopefully the scientific community and the media will demand that it is accompanied by a complete set of documents, including details of the systematic analysis and sufficient data to enable objective verification."

Reminded me of so many of the entries you and Anne make on this thoughtful, informative and inspiring blog.

Ed

Ken Weiss said...

Thanks. Like any aspect of human culture, we make our imperfect way in the world, we have our self-interests and our blinkers. One may just say that in the long run, we're all ant food and it doesn't really matter. But if we let ourselves just say this just-how-things-are, we acquiesce. Sometimes, that allows the creep of initially innocuous ideas or practices to become horrific abuses.

If we object, raise awareness, and so on, some change or improvement may occur. At least we would have the satisfaction of having tried. And, of course, if the majority don't think there's a problem, nobody will change. And we'll still regularly be misinformed and misled about the nature of things....